In recent years, advances in ink-jet technology have been remarkable and together with improvements in printer technology, ink technology and exclusive recording media technology, made ink-jet images to be called as photographic images. As image quality improves, storage stability of ink-jet images has come to be compared with that of conventional silver salt photography, and, with respect to many dye inks, deterioration accompanied by migration of colorants such as poor water resistance and anti-bleeding property of ink-jet images, or accompanied by a chemical reaction characteristic to colorants such as poor light fastness and anti-oxidizing gas resistance, has been pointed out.
On the other hand, in order to improve storage stability of dye ink images, utilization of a pigment ink has been often proposed. However, it is not preferable that glossy appearance similar to that of silver salt photography may not be obtained and metallic gloss called bronzing may be observed in case of pigment inks. Further, only utilizing pigment inks can not achieve sufficient storage stability of images and in particular weakness of water fastness is remarkable.
In JP-A 2000-158803 (the term, JP-A refers to an unexamined and published Japanese Patent Application), a method to improve water resistance, light fastness and gloss has been proposed by recording with a pigment ink onto a recording medium having a layer comprised of thermoplastic organic fine particles and being followed by heat fixing. However, the gloss level was not sufficient and still inferior to that of silver salt photography, and water resistance was also insufficient. In addition, appearance of bronzing was observed which was not preferable, and it was not satisfactory in respect to oxidizing gas resistance. Consequently, urgent improvement has been demanded.